Digoxin, Serum
Use
Digoxin is widely prescribed for the treatment of congestive heart failure and various disturbances of cardiac rhythm. It improves the strength of myocardial contraction, resulting in increased cardiac output, decreased heart size, decreased venous pressure, and decreased blood volume. Monitoring digoxin therapy is critical due to its narrow therapeutic window and the potential for toxicity, which can cause symptoms mimicking the cardiac arrhythmias for which digoxin is prescribed.
Special Instructions
Patient preparation is critical; for 12 hours before specimen collection, do not take multivitamins or dietary supplements containing biotin (vitamin B7). It is vital to draw the blood 6 to 8 hours after the last dose of digoxin for accurate measurement.
Limitations
Patients vary in their responsiveness to digoxin, and renal dysfunction can lead to an accumulation of the drug in the serum. The assay measures both bound and free digoxin, leading to high values in patients receiving digibind therapy. Digoxin-like immunoreactive factors may cause falsely elevated values in some neonates and patients with advanced liver or renal disease.
FDA ApprovedNew York Approved
Methodology
Immunoassay (ECLIA)
Biomarkers
LOINC Codes
- 83093-5
- 83093-5
Result Turnaround Time
1-2 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.5 mL
Container
Plastic vial
Collection Instructions
Draw blood 6 to 8 hours after the last dose of digoxin. Centrifuge serum gel tubes within 2 hours of collection. Centrifuge red-top tubes and aliquot serum into a plastic vial within 2 hours of collection.
Patient Preparation
For 12 hours before specimen collection, do not take multivitamins or dietary supplements containing biotin (vitamin B7).
Causes for Rejection
Gross hemolysis
Stability Requirements
| Temperature | Period |
|---|---|
| Refrigerated | 7 days |
| Frozen | 180 days |